Digital Commons Network^™

Microbiome Assembly And Function In The Solitary Mason Bee, Osmia Lignaria (Megachilidae), Bailey Crowley

All Graduate Theses and Dissertations, Fall 2023 to Present

Animal-microbe interactions can influence host biology, ecology, and evolution. The assembly and function of microbes found within animal hosts oftentimes depends on which species are involved. Advances in sequencing technologies have permitted the exploration of host-microbe interactions in a variety of animals, including bees. Early research aimed at understanding the microbiomes of social bees, such as honey bees and bumble bees, found that microbes prevent the spoilage of stored pollen, breakdown indigestible nutrients into smaller molecules available for uptake by the host, and also protect the host from pathogens. When environmental stressors, such as increased temperatures, disrupt the microbiome, the …

The Interactions Between Drought Tolerant Corn Hybrids And Plant Water-Stress On Weeds And Their Host Capability For Spider Mites, Mercy Adhiambo Odemba

All Graduate Theses and Dissertations, Fall 2023 to Present

With climate change, it is predicted that more frequent high temperatures and drought severity will lead to an increase in damage caused by pests that thrive under these conditions. Spider mite outbreaks, for example, are associated with plant waterstress and there is evidence that some weeds are more resilient and adapted to drought than some crops, leading to major concerns for the management of these two pest types. Weeds directly compete with crops for limited resources, but what is unclear is which weeds harbor spider mites and whether they exacerbate the impact of spider mites on corn crops under water-stressed …

The Stability Of Epigenetic Variants That Can Act As Loci Causing Phenotypic Change, Raul Faburrieta

Biology Theses

Epigenetic variations are a possible source of heritable phenotypic variation. In this study I focus on phenotypic alterations seen in epigenetic Recombinant Inbred Lines (epiRILs) of Arabidopsis thaliana. These epiRILs allow me to study the effects differentially methylated regions (DMRs) have on phenotypic variance. In a study performed in 2014 by Cortijo et al., they found that DMR’s affect flowering time and root length when grown under greenhouse conditions. In this study, I replicated the Cortijo et al. (2014) study, with some changes, to see whether the same significant eQTL regions are found. I found that, some of the eQTLs …

Towards A New Role Of Mitochondrial Hydrogen Peroxide In Synaptic Function, Cliyahnelle Z. Alexander

Student Theses and Dissertations

Aerobic metabolism is known to generate damaging ROS, particularly hydrogen peroxide. Reactive oxygen species (ROS) are highly reactive molecules containing oxygen that have the potential to cause damage to cells and tissues in the body. ROS are highly reactive atoms or molecules that rapidly interact with other molecules within a cell. Intracellular accumulation can result in oxidative damage, dysfunction, and cell death. Due to the limitations of H₂O₂ (hydrogen peroxide) detectors, other impacts of ROS exposure may have been missed. HyPer7, a genetically encoded sensor, measures hydrogen peroxide emissions precisely and sensitively, even at sublethal levels, during …

Screen For Beneficial Genetic And Chemical Modifiers In Drosophila Models Of Als And Traumatic Brain Injury, Will Bonderer

Biological Sciences Theses and Dissertations

The underlying molecular processes of aberrant protein expression in neurodegeneration are intricate and multifaceted, with ribosome-associated quality control (RQC) emerging as a promising avenue of exploration. Ribosome-associated quality control is integral to cellular function. Its evolutionarily conserved pathway encompasses a network of mechanisms designed to ensure the fidelity of protein synthesis, folding, and degradation within the cells of all eukaryotes. The ribosome, central to protein synthesis, plays a pivotal role in this quality control network, and its malfunction can lead to the accumulation of misfolded or aberrant proteins. In the context of neurodegenerative disorders, this dysfunction can have dire consequences. …

Patterns And Potential Mechanisms Of Phenotypic Changes In Urban Small Mammals, Leslie Lopez

Master's Theses

Urbanization is an example of human induced rapid environmental change that can have wide-reaching ecological effects, including habitat destruction, fragmentation, and alteration of local climates. Effects of urbanization have been shown to impact wildlife, as disturbances resulting from urbanization can create novel environments and selective pressures that could lead to changes in morphology, physiology, or both. Small mammals such as rodents are an ecologically important set of wildlife species because they are a key prey item for several predators, hold strong influence over plants as a primary consumer, and some species carry and transmit major human and animal diseases. Previous …

The Development Of Immunohistochemistry (Icc) And Transcriptomic Protocols To Uncover Neurophysiological Markers Of Stress In Red-Eyed Tree Frogs As A Novel Biome, Shirin Dadina

Senior Theses and Projects

Adverse childhood experiences (ACEs) include various forms of physical and emotional abuse that lead to detrimental long term effects. Agalychnis callidryas (red-eyed tree frogs) have been identified as a novel biomedical model for ACEs. Red-eyed tree frogs demonstrate an escape hatch mechanism under stressors including those from predators, flooding and hypoxia where the embryo undergoes an accelerated developmental process similar to what is observed in the human population regarding precocious puberty. In order to assess this model for neurobiological outcomes of ACEs, morphological and genomic protocols must be developed and validated which is this study’s focus. Paraffin embedding and microtome …

Role Of Integrase-Pp2a Interaction In Human T-Cell Leukemia Virus Type-1 Replication And Pathogenesis, Shayna Turbin

Senior Honors Papers / Undergraduate Theses

Human T-cell leukemia virus type-1 (HTLV-1) is an oncogenic retrovirus that causes multiple disorders, including adult T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis. HTLV-1 retroviral integrase binds to the regulatory B’56γ subunit of the host cell Protein Phosphatase 2A (PP2A). Integrase contains a highly conserved LxxIxE motif that is essential for binding, which increases integration efficiency and facilitates HTLV-1 hijack of host cell machinery. We aim to understand how mutations introduced in the highly conserved binding site can affect viral particle production and infectivity. We transfected 729B human lymphoblastoid cells and 293T cells with mutant and wildtype virus. Mutations L213A, …

Measuring The Effects Of Selenium Exposure On Batrachochytrium Dendrobatidis (Bd) Growth In Vivo In Larval American Bullfrogs (Rana Catesbeiana)., Taylor Morrison

Honors Thesis

Most amphibians in today’s world are exposed to a variety of environmental stressors. This project’s main objective was to determine any effects of selenium on Batrachochytrium dendrobatidis (Bd) and infection levels in South Dakota amphibians. I selected American bullfrogs (Rana catesbeiana) as they are susceptible to Bd and are found throughout eastern South Dakota. The secondary objective of this project was to measure any impact of Bd and selenium, combined, on growth measures of the frogs. The third objective was to see if survival rates were reduced when amphibians were exposed to Bd and selenium. Tadpoles were collected (n=225) from …

Isolation Of Aged Mouse Primary Microglia As A Model System For Alzheimer’S Disease Research, Michael Landis

Biology Honors Papers

Microglia and their role as the immune cells of the central nervous system are an emerging area of interest within Alzheimer’s research, particularly as they have shown in a benevolent and malevolent cellular context. Models of Alzheimer’s disease are very light in studying microglia, so in this study a model of microglia isolated from aged mice is established in order to study the phagocytic activity and protein expression of microglia in response to Amyloid Beta. The cells were isolated from aged mice and cultured before being used to confirm cellular identity, as well as to measure phagocytic activity. This study …

Clonal Plants' Traits And Responses Following Fire Disturbance In Ponderosa Pine Ecosystems In The Colorado Front Range, Raymond Erskine

Master's Theses

Mountain ecosystems are currently experiencing increasing impacts of disturbances (e.g., wildfire) due to global changes in climate and land use, leading to significant changes in vegetation composition and landscape dynamics. Clonal plants, characterized by their vegetative reproduction strategies, offer a range of ecologically important traits to cope with disturbances. However, clonality is often excluded in studies of post-fire vegetation dynamics in mountain ecosystems, and our knowledge of the ability of clonal plants to respond to differing disturbance regimes is limited. Therefore, I examined the response of understory vegetation following fire disturbance in burned and unburned ponderosa pine stands of the …

Mate Guarding Against Strong Men Displaying Affiliative And Aggressive Humor, Jacob Pauley

Biological Sciences Undergraduate Honors Theses

Mate retention behaviors serve to discourage partner defection from a current pairbond. Such behaviors are oftentimes more prevalent toward intrasexual rivals exhibiting physical and behavioral cues implicating that rival as an optimal mate. Among these features in men are their upper body strength, a feature diagnostic of heritable fitness, and men's ability to produce humor, a cue to their social competence. This study considered the intersection of these desirable features in shaping men's mate retention behavior toward an intrasexual rival. After learning of a hypothetical interloper exhibiting high or low upper body strength while similarly using humor in an affiliative …

Towards Understanding The Function Of An Ets-Like Gene In Nematostella Vectensis: Generation Of A Knockout Mutant Line And A Transgenic Reporter Line, Emily Bullock

Biological Sciences Undergraduate Honors Theses

Due to their unique phylogenic position as sister to Bilateria, Cnidaria are often credited with the utility of allowing for reconstruction of ancestral biology based on characteristics shared with bilaterians and other animals. This factor makes investigation into the nervous systems of cnidarians critical in understanding early neural evolution. Wamides, a class of neuropeptides, have been shown to play a regulatory role in life cycle transitions across many different species. The cnidarian specific Wamide neuropeptide, GLWamide, has previously been identified to play an accelerator role in the metamorphic timing of a specific species of sea anemone, Nematostella vectensis. However, …

Effect Of Progesterone On Cognition Among College Aged Women, Katelyn Helberg

Biological Sciences Undergraduate Honors Theses

Women who have a reoccurring menstrual cycle and do not take hormonal birth control naturally experience changes in the amount of sex hormones that their body produces. These sex hormones help promote sexual development, fertility, and mood regulation, but can be hard to study due to their conflicting effects on each other. One such hormone, progesterone, is produced in different concentrations throughout the menstrual cycle to prepare the uterus for a potential pregnancy. However, it also may have secondhand effects on how well women can complete everyday tasks involving memory, attention, processing speed, and more which is what we measured …

Biophysical Model Of Retraction Motor Neurons And Their Modification By Operant Conditioning, Maria Rasheed

Dissertations & Theses (Open Access)

Operant conditioning (OC) is a form of associative learning in which an animal modifies its behavior based on the consequences that follow that behavior. Despite its ubiquity, the underlying mechanisms of OC are poorly understood. Insights into the mechanisms of OC can be obtained by studying Aplysia feeding behavior as it can be modified by OC. This behavior is mediated by a central pattern generator (CPG) network in the buccal ganglia that contains a relatively small number of neurons. This CPG generates rhythmic motor patterns (BMPs) that move food into the gut by closing a tongue-like structure (i.e., radula) during …

The Effect Of Hormonal Contraceptive Use On Dominance And Prestige Tactics, Carson Chappell

Biological Sciences Undergraduate Honors Theses

This study was designed to investigate the relationship between hormonal contraceptives and prestige and dominance status-seeking tactics. Existing literature has examined how the hormones estrogen and progesterone, especially in relation to the fertile window of the menstrual cycle, are associated with prestige and dominance but has yet to look in depth at how hormonal contraceptives might alter this impact. The current study asked participants to complete a 22- item questionnaire assessing dominance and prestige. I hypothesized that women on hormonal contraceptives would have lower scores for prestige and dominance compared to women who are naturally cycling. The results did not …

The Optimal Timing Of Abscisic Acid Treatment In Arabidopsis Under Drought And Salt Stress, Khelia Gihozo

Graduate Student Dissertations, Theses, Capstones, and Portfolios

As climate change intensifies, harsh environmental conditions, such as increased drought and salt levels, will pose significant challenges to agricultural productivity globally. It is important to develop strategies for plants to tolerate these adverse conditions. This study aims to investigate how well the timing of abscisic acid (ABA) treatment can promote resistance to salt and drought in Arabidopsis thaliana grown on Murashige and Skoog agar medium. The study evaluates both wild-type and transgenic lines overexpressing the DREB2A gene, a transcriptional activator involved in the stress response of plants. Plants were exposed to drought and salt stress as they matured. Followed …

Utilizing Biomimicry To Design Sustainable Architecture, Virginia Hammond

Architecture Undergraduate Honors Theses

Nature has an integral relationship with architecture and serves as a sustainable role model and inspiration for designers. The process of biomimicry in architecture has the potential to produce more sustainable design solutions and foster a connection between humans and nature. Existing biomimetic design projects have varying strengths and weaknesses as examples of the process. Utilizing guidelines and references from key leaders in biomimetic design consultancy (Biomimicry 3.8), selected case studies are assessed for their ability to demonstrate the benefits of this design strategy. Using these evaluations, the case studies are diagrammed and critiqued to determine how new projects could …

Qualitative Assessment Of Human Embryonic- And Induced Pluripotent Stem Cell Derived Neural Stem Cells Under Cgmp Methods, Michelle Hernandez

Electronic Theses, Projects, and Dissertations

Neural stem cell therapies represent a promising tool for the development of regenerative medicine and are being tested in clinical trials for several neurological disorders. However, the clinical applicability of stem cell therapies is dependent on the implementation of current good manufacturing practices (cGMPs) to ensure the quality, safety, and consistency that stem cell products need to meet FDA regulatory requirements. As such, there is a need for a shift to xeno-free methodologies so experimental conditions are cGMP compliant. The purpose of this study is to test a GMP compatible production method to generate multipotent neural stem cells (NSCs) from …

Survey Of The Bolctes From Fish River Nature Preserve, Noah T. Nelson

Honors Theses

Boletes are a special kind of mushroom inside of the Kingdom Fungi that are distinguished from other mushrooms by their uniquely pored hymenium, as opposed to gills. Many boletes are ectomycorrhizal, meaning they are mutualists with vascular plants, and thus beneficial to the overall health of the terrestrial ecosystem. Some are well-known for their edibility and are of economic importance. In the United States 59 genus-level clades comprising 290 operational taxonomic units have been reported. The southeastern US and Gulf Coast regions however are less researched and recorded for their mushroom ecology. In Alabama, only 56 bolete species have been …

Survival Of Methanogens Desiccated On Mars Soil Simulants: Implications For Life On Mars, Lanee Knight

Biological Sciences Undergraduate Honors Theses

Because of Mars’s chemical features, it can be studied in the search for life and is a significant figure in the study of astrobiology (McKay, 2010). Dr. Kral’s laboratory studies methanogens, microorganisms in the domain Archaea, as possible life forms on Mars. Since some methanogens can withstand harsh environmental conditions and emit methane as a waste product, the growth of these microorganisms can be used as an indicator of potential life in the Mars subsurface (Kral et al., 1998). In this research, four methanogens, Methanothermobacter wolfeii, Methanobacterium formicicum, Methanosarcina barkeri, and Methanococcus maripaludi were desiccated in the …

Gopher Tortoises In Protected Natural Areas: Effects Of Natural Area Characteristics On Populations, Taryn Lagor

Graduate Student Dissertations, Theses, Capstones, and Portfolios

The gopher tortoise (Gopherus polyphemus) is native to the Southeast region of the United States. The burrows it digs supports the survival and wellbeing of over 350 other species, with over 60 of those being other vertebrates, making it a keystone species. It is ranked threated to rare by differing organizations with the main threat throughout its entire natural range being habitat loss. The Florida Scrub is the natural habitat of Florida gopher tortoise populations and is one of the fastest declining ecosystems in Florida, particularly in South Florida, due to rapid urban development. Many of the remaining …

Reactive Oxygen Species Production In Head Regeneration Of Planaria From Cadmium Exposure, Natalie Gonzalez

Graduate Student Dissertations, Theses, Capstones, and Portfolios

Exposure to cadmium, a pervasive neurotoxic chemical found in our environment, poses significant health risks, disrupting various physiological systems and fostering carcinogenesis. Commonly found in everyday items like cigarettes, batteries, and plastics, cadmium disrupts the equilibrium between reactive oxygen species (ROS) production and cellular repair mechanisms, culminating in oxidative stress and potential cell damage. In toxicological and pharmaceutical research, planarians offer valuable insight for understanding how exposure to chemicals akin to human scenarios can alter biological systems. This experiment addresses the effect cadmium chloride (CdCl₂) has on planarian regeneration and whether antioxidants can mitigate those adverse outcomes. Our …

Syntaxin-3 Mediates Baseline And Stimulated Mucin Secretion, Brianne Wharton

Dissertations & Theses (Open Access)

There are two rates at which airway epithelial cells secrete mucin. The low baseline rate accounts for ciliary clearance, and the high stimulated rate obstructs airways in protection from helminths or in obstructive pulmonary diseases. The exocytosis of mucins occurs via the four-helix SNARE complex. The SNARE proteins contributing helices are the vesicle-SNARE VAMP, and the target-SNAREs SNAP and Syntaxin. Coiling of the complex fuses the granule and plasma membranes to release mucins into the extracellular space. The VAMP and SNAP isoforms mediating baseline and stimulated secretion are known, but the Syntaxin (Stx) isoform remains unknown.

Three candidate exocytic Stx, …

The Influence Of Researcher Disturbance On Raccoon Predation Of American Alligator Nests, Clarissa Tuten

Electronic Theses and Dissertations

Raccoons (Procyon lotor) are a dominant predator of American alligator (Alligator mississippiensis) nests in the southeastern United States, using a combination of olfactory, visual, and tactile cues to identify nest locations. Studies on alligator nesting ecology typically require researchers to create paths through marsh habitat, potentially introducing visual and olfactory cues raccoons may use to locate nests. The purpose of this study was to evaluate the effect of human visitation to alligator nests on the frequency of raccoon nest predation at two sites in coastal South Carolina, Tom Yawkey Wildlife Center (TYWC) and Santee Coastal Reserve (SCR). We hypothesized that …

Growth Of Methanogens On Kaolinite, A Clay That Has Been Identified On Mars, Hailey Littrell

Biological Sciences Undergraduate Honors Theses

Methanogens have been studied as a model for life on Mars for 28 years now in the Kral lab. The discovery of methane in the Martian atmosphere by ground-based and orbital observations as well as Curiosity Rover (Formisano, V. et al., Krasnopolsky, V.A. et al., Mumma, M.J. et al.) has added relevance to these types of studies. Methanogens were chosen due to their ability to live in harsh environments, very similar to the Martian terrain. In addition to methane in the atmosphere, phyllosilicate clays have also been identified. One of those clays is kaolinite. Kaolinite has been found to not …

From Cells To Clinics- The Role Of College Biology Education In Shaping Future Physician Assistants, Monica Manley

Honors Theses

This thesis provides a personal reflection on translating concepts and techniques learned in multiple biology courses (i.e. microbiology, neuroscience, comparative physiology, and genetics) in to clinical practice as an intern in the emergency room of a hospital. Each selected concept contains a description followed by an example of how this knowledge relates to a specified duty of a physician assistant with in an emergency medical setting.

Clonal Growth And Trait Variation In The Colorado Front Range: The Influence Of Elevation And Ecosystem, Jordan Conley

Master's Theses

Amid global climate change, exploring adaptive strategies among alpine flora, particularly through clonal growth, becomes critical for biodiversity conservation. This study aims to explore the patterns of dominance and distributions among clonal species across environmental gradients in the Colorado Front Range, employing a trait-based comparative analysis to understand the adaptive strategies of alpine flora and their implications for conservation amid rapid climate change. We focused on two species, studying traits like lateral spread, bud count, and bulbil numbers. Advanced statistical methods such as Permutational Multivariate Analysis of Variance (PerMANOVA) and Multi-Response Permutation Procedures (MRPP) were used to evaluate community compositions …

Pipecolic Acid And Novel Insights Into Cerebral Malaria, Akua E. Mensah

Theses

Cerebral malaria (CM), a severe manifestation of Plasmodium infection, prompts our investigation into the nuanced role of pipecolic acid in its pathophysiology. To unravel the molecular intricacies, we conducted in vitro lysine labeling techniques of mice infected with P. berghei ANKA parasites, and human P. falciparum grown in vitro, aiming to discern the impact of Plasmodium on pipecolic acid production. Previous observations indicated an elevation in pipecolic acid levels correlating with neurological decline in children with CM. In our study, confirming elevated pipecolic acid presence in the plasma and brain tissues of CM patients and the animal model of CM, …

Spatial Ecology Of Mule Deer Migrations From Grand Teton National Park And The Teton Range, Justin K. Schwabedissen

All Graduate Theses and Dissertations, Fall 2023 to Present

The Greater Yellowstone Ecosystem hosts several of the longest, fully intact ungulate migrations remaining in the continental United States. However, expanding development and an increasing human footprint continue to truncate migratory routes. While the endpoints are often a seasonal range on protected lands, these migration corridors frequently cross other jurisdictional boundaries, including large tracts of private or multiple-use lands, with varying levels of protection. Thus, it is critical resource managers understand the dynamics of migratory movements to define population-level corridors and prioritize appropriate conservation strategies. Mule deer in Wyoming have been documented traveling long distances between summer and winter ranges; …